Actual size: 19.5 x 19.5 x 0.75 inches
Pleated air filters suitable for furnaces, ACs and residential HVAC systems
MERV 11 filters remove up to 95% of common particles including fine dust, smoke, and smog particles. These filters reduce allergy symptoms and protect against outdoor air pollution.
Processed quickly, ships fast, free for all orders
Premium quality products crafted right here at home
Return your items within 30 days and get a full refund
Find your perfect fit with our complete size range
MERV 11 air filters are designed for homes with allergies and in some cases, asthma. Those with respiratory illnesses or compromised immune systems may benefit from MERV 11 air filters due to these filters being significantly more powerful than alternative MERV filters at capturing smaller particles, such as MERV 8.
Scroll right to see more
Check the label on your current filter or use a tape measure to get the exact length, width, and depth before selecting your size.
Nominal size
Nominal size is what you normally see printed on the label. This is usually a rounded size which is often not the true size of your filter.
Actual size
Actual size is the true size of the air filter, usually written in smaller font below the nominal size.
Measure your current air filter or the length, width, and depth of the opening slot to get the actual size. Round it up to the nearest whole inch to get the nominal size.
Installing 20x20x1 air filters couldn't be easier. Just make sure to align the arrow printed on the side with the airflow direction!
Remove the air filter from the package
Locate the arrow and point it in the direction of the fan
Slide the filter in to the slot of the central unit
For return grills, insert the filter into the grill, pointing the arrow inwards
For best indoor air quality, we recommend you change your filters regularly at different times depending on your situation.
Replace your air filter every 6 weeks to minimize the circulation of bacteria and allergens in the air.
Replace air filters every 2 months to reduce odors as well as pet dander and hair buildup in your system.
Replace your air filter every 2-3 months to reduce airborne particles and maintain cleaner indoor air.
Keeping your air filter replacement schedule in mind can be challenging to say the least. Make your life easier with Filter King's auto delivery.
No, you cannot use a 20x20x2 air filter in a slot designed for 20x20x1. This is an improper size for the opening and will be too thick, which can strain your HVAC unit. This can cause damage overtime. In addition, it won't clean the air properly if it's improperly sized for your space. It doesn't save you anything much less money to have an improperly fitted filter either.
No, you cannot wash or reuse your 20x20x1 pleated filter from Filter King.
Yes, a higher MERV 20x20x1 filter can make your system work harder. But, if your home is modern and your unit is new, it might be able to handle the extra filtration. If you want to improve your indoor air quality by increasing your filter rating, just make sure you check your unit guidelines and recommendations first.
Well, by industry standards, these are the same thing. However, Filter King does offer a true-to-size filter that is designed for superior filtration. This also means your filter will fit perfectly as designed in your space as constructed and will reduce dust, pollen and more.
During the winter months, your HVAC system is likely to run much more frequently in order to keep your home comfortable. This means that, based on the increased use or your specific needs, you will likely need to opt for filter replacement more often. This is normal. Dust buildup along with even more pollen can be common as well.
No. The number of pleats will depend on the MERV rating, among other factors. So, not all filters have the same number of pleats.
MERV 8 filters